First Arrivals

A medium SQL interview practice problem on DataDriven. Write and execute real sql code with instant feedback.

Domain

SQL

Difficulty

medium

Seniority

L5

Problem

For each calendar date, how many customers placed their very first order on that day? A customer's first-order date is the earliest order they have in the table.

Summary

Every customer has a first day. Find when the crowds showed up.

Practice This Problem

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